Improve code word interference cancellation (CWIC) technique in heterogeneous network
This paper first examines performance of (code word interference cancellation) CWIC for downlink non orthogonal multiple access (NOMA) combined with 2-by-4 multi-user (MU)-MIMO, taking into account the disadvantages of the CWIC receiver, such as complex receiver structure, high volumes of network overhead and high delay, we offer a way to improve the efficiency of the CWIC receiver. CWIC receiver detects, decodes and cancels all interference signals in several steps, from large to small, respectively. The number of interference cancellation stages depends on the number of interference signals. The proposed receiver only cancels the intense interference signal. That's why it's called CWIC-II (Intense Interference). Finally, using simulation, we show that CWIC-II receiver reduces latency and improves throughput. The complexity problem of the CWIC receiver structure is also resolved. In the end, a method has been developed to resolve the problems of the proposed receiver.
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